CN103218976B - LED backlight driving circuit, LED backlight and liquid crystal display - Google Patents
LED backlight driving circuit, LED backlight and liquid crystal display Download PDFInfo
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- CN103218976B CN103218976B CN201310069884.1A CN201310069884A CN103218976B CN 103218976 B CN103218976 B CN 103218976B CN 201310069884 A CN201310069884 A CN 201310069884A CN 103218976 B CN103218976 B CN 103218976B
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- 239000004973 liquid crystal related substance Substances 0.000 title claims abstract description 17
- 239000003990 capacitor Substances 0.000 claims description 52
- 230000001105 regulatory effect Effects 0.000 claims description 8
- 230000003292 diminished effect Effects 0.000 claims description 6
- 230000003247 decreasing effect Effects 0.000 claims description 3
- 238000000034 method Methods 0.000 abstract description 4
- 238000001228 spectrum Methods 0.000 abstract description 4
- 239000006185 dispersion Substances 0.000 abstract description 3
- 238000005516 engineering process Methods 0.000 description 3
- 230000001276 controlling effect Effects 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 1
- 239000012141 concentrate Substances 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 238000004020 luminiscence type Methods 0.000 description 1
- 229910044991 metal oxide Inorganic materials 0.000 description 1
- 150000004706 metal oxides Chemical class 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
Classifications
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- G—PHYSICS
- G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
- G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
- G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
- G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
- G09G3/34—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source
- G09G3/3406—Control of illumination source
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B45/00—Circuit arrangements for operating light-emitting diodes [LED]
- H05B45/20—Controlling the colour of the light
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- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Computer Hardware Design (AREA)
- General Physics & Mathematics (AREA)
- Theoretical Computer Science (AREA)
- Circuit Arrangement For Electric Light Sources In General (AREA)
- Dc-Dc Converters (AREA)
Abstract
The present invention discloses a kind of LED backlight driving circuit, LED backlight and liquid crystal display.This LED backlight driving circuit comprises: DC voltage input end, for input direct voltage; Booster circuit, the DC voltage for being inputted by DC voltage input end is carried out boosting and is exported voltage boosting dc voltage; LED strip, comprises multiple LED and first resistor of series connection, and LED strip receives voltage boosting dc voltage from booster circuit, and wherein, the DC voltage of LED strip normal luminous is less than or equal to the voltage boosting dc voltage of booster circuit output; Constant-current drive circuit, according to the voltage at the first resistor two ends and the voltage of triangular signal, outputs level signals is to booster circuit.By making the frequency of drive singal change back and forth near centre frequency, the spectrum energy of dispersion drive singal, in EMI test process, is not easy to occur that the peak value of drive singal exceeds standard situation, improves EMI test result.
Description
Technical field
The invention belongs to field of liquid crystal display.More particularly, a kind of LED backlight driving circuit, LED backlight and liquid crystal display is related to.
Background technology
Along with the continuous progress of technology, the backlight technology of liquid crystal display is constantly developed.The backlight of traditional liquid crystal display adopts cold-cathode fluorescence lamp (CCFL).But due to CCFL backlight have that color restoration capability is poor, luminescence efficiency is low, under sparking voltage high and low temperature poor, the heating of flash-over characteristic reach the shortcomings such as the stable gray scale time is long, currently developed the back light source technique using LED backlight.
But in existing LED backlight driving circuit, the frequency of drive singal that constant-current drive circuit exports is fixed, and its spectrum energy concentrates on the harmonic frequency point of first-harmonic, in EMI(electromagnetic interference (EMI)) in test, be easy to the situation occurring that peak value exceeds standard, be unfavorable for EMI test result.
Summary of the invention
In order to solve above-mentioned problems of the prior art, the object of the present invention is to provide a kind of LED backlight driving circuit, comprise: DC voltage input end, for input direct voltage, booster circuit, DC voltage for being inputted by DC voltage input end is carried out boosting and is exported voltage boosting dc voltage, LED strip, comprise multiple LED and first resistor of series connection, and receive voltage boosting dc voltage from booster circuit, wherein, the DC voltage of LED strip normal luminous is less than or equal to the voltage boosting dc voltage of booster circuit output, constant-current drive circuit, according to the voltage at the first resistor two ends and the voltage of triangular signal, outputs level signals is to booster circuit.
In addition, described constant-current drive circuit comprises: triangular-wave generator, for generation of triangular signal, 3rd comparer, for comparing the voltage of triangular signal and the voltage at the first resistor two ends, wherein, the negative terminal of the 3rd comparer receives the voltage of triangular signal, the anode of the 3rd comparer receives the voltage at the first resistor two ends, when the voltage of triangular signal is greater than the voltage at the first resistor two ends, the output terminal of the 3rd comparer exports the first level signal to booster circuit, when the voltage of triangular signal is less than the voltage at the first resistor two ends, the output terminal of the 3rd comparer exports second electrical level signal to booster circuit.
In addition, described booster circuit comprises inductor, the 3rd MOS transistor, commutation diode and the second capacitor, wherein, one end of inductor is for receiving described DC voltage, the other end of inductor is connected to the positive pole of commutation diode, the drain electrode of the 3rd MOS transistor is connected between inductor and the positive pole of commutation diode, one end of second capacitor is connected to the negative pole of commutation diode, the other end of the second capacitor is connected to the source electrode of the 3rd MOS transistor, and the grid of the 3rd MOS transistor is connected to constant-current drive circuit.
In addition, described triangular-wave generator comprises: variohm, first MOS transistor, first comparer, second comparer, first capacitor, second resistor, second MOS transistor, wherein, one end of variohm receives input voltage, the other end of variohm is connected to the drain electrode of the first MOS transistor, the source electrode of the first MOS transistor connects one end of the second resistor and is connected to the negative terminal of the 3rd comparer, the other end of the second resistor is connected to the drain electrode of the second MOS transistor, the source electrode electrical ground of the second MOS transistor, the grid of the first MOS transistor is connected to the output terminal of the first comparer, the grid of the second MOS transistor is connected to the output terminal of the second comparer, the negative terminal of the first comparer connects one end of the first capacitor and is connected to the source electrode of the first MOS transistor, the other end electrical ground of the first capacitor, the anode of the first comparer receives the first reference voltage, the negative terminal of the second comparer is connected to the output terminal of the first comparer, the anode of the second comparer receives the second reference voltage.
In addition, by regulating the size of described input voltage to regulate the size of the frequency of described triangular signal, wherein, when input voltage becomes large, the charging current of the first capacitor becomes large, the charging voltage of the first capacitor becomes large, the rate of rise of triangular signal is made to become large, namely the frequency of triangular signal becomes large, when input voltage diminishes, the charging current of the first capacitor diminishes, and the charging voltage of the first capacitor diminishes, the rate of rise of triangular signal is diminished, and namely the frequency of triangular signal diminishes.
In addition, also the size by regulating the size of resistance of variohm to regulate the frequency of described triangular signal, wherein, when the resistance decreasing of variohm, the charging current of the first capacitor becomes large, the charging voltage of the first capacitor becomes large, the rate of rise of triangular signal is made to become large, namely the frequency of triangular signal becomes large, when the resistance of variohm becomes large, the charging current of the first capacitor diminishes, and the charging voltage of the first capacitor diminishes, the rate of rise of triangular signal is diminished, and namely the frequency of triangular signal diminishes.
In addition, described first level signal is low level signal, and described second electrical level signal is high level signal.
In addition, described DC voltage is converted to by the alternating voltage of liquid crystal display outside.
Another object of the present invention is also to provide a kind of LED backlight, and this LED backlight comprises above-mentioned LED backlight driving circuit.
Another object of the present invention is also to provide a kind of liquid crystal display, comprises display panels and above-mentioned LED backlight, and wherein, display panels is placed on described LED backlight.
According to LED backlight driving circuit of the present invention, LED backlight and liquid crystal display, change back and forth near centre frequency by making the frequency of drive singal, the spectrum energy of dispersion drive singal, in EMI test process, be not easy to occur that the peak value of drive singal exceeds standard situation, improve EMI test result.
Accompanying drawing explanation
Fig. 1 illustrates LED backlight driving circuit according to an embodiment of the invention.
Fig. 2 illustrates booster circuit in LED backlight driving circuit according to an embodiment of the invention and constant-current drive circuit.
Fig. 3 illustrates triangular-wave generator according to an embodiment of the invention.
Fig. 4 illustrates liquid crystal display according to an embodiment of the invention.
Embodiment
Be described in detail the embodiment of the present invention now, its sample table shows in the accompanying drawings, and wherein, identical label represents same parts all the time.Be described to explain the present invention to embodiment below with reference to the accompanying drawings.In the following description, obscuring of the present invention's design that the unnecessary detailed description in order to avoid known features and/or function causes, can omit the unnecessary detailed description of known features and/or structure.
Fig. 1 illustrates LED backlight driving circuit according to an embodiment of the invention.
As shown in Figure 1, LED backlight driving circuit comprises DC voltage input end 11, booster circuit 12, LED strip 13 and constant-current drive circuit 14 according to an embodiment of the invention.
DC voltage input end 11 is for input direct voltage (such as, 24V), and this DC voltage is converted to by electric main pressure (such as, 110V or 220V).Such as, can utilize the AC-DC change-over circuit of prior art that electric main pressure is converted into DC voltage.
The DC voltage that DC voltage input end inputs is carried out boosting and is exported voltage boosting dc voltage by booster circuit 12.
LED strip 13 is arranged in the rear of the display panels of liquid crystal display as backlight, and LED strip 13 comprises multiple LED and the first resistor R1 of series connection.This LED strip 13 receives voltage boosting dc voltage from booster circuit 12.The quantity N(N of the LED in LED strip 13 be greater than zero integer) determined as follows:
N×Vd≤Vs，
Wherein, Vd is the luminous voltage of each LED, and Vs is the voltage boosting dc voltage that booster circuit 12 exports.
Such as, when Vd is 5.5V, Vs=60V, N≤10.
Alternatively, the first resistor R1 can not be comprised in LED strip 13.
Constant-current drive circuit 14 is for the voltage of the voltage (i.e. the voltage of LED strip 13 negative terminal) according to the first resistor R1 two ends and triangular signal, and outputs level signals is to booster circuit 12.This level signal namely drives booster circuit 12 to provide the drive singal of described voltage boosting dc voltage to LED strip 13.
Fig. 2 illustrates booster circuit in LED backlight driving circuit according to an embodiment of the invention and constant-current drive circuit.
As shown in Figure 2, booster circuit 12 comprises according to an embodiment of the invention: inductor L, 3rd metal-oxide semiconductor (MOS) (MOS) transistor Q3, commutation diode D and the second capacitor C2, wherein, one end of inductor L is for receiving described DC voltage, the other end of inductor L is connected to the positive pole of commutation diode D, the drain electrode of the 3rd MOS transistor Q3 is connected between the positive pole of inductor L and commutation diode D, one end of second capacitor C2 is connected to the negative pole of commutation diode D, the other end of the second capacitor C2 is connected to the source electrode of the 3rd MOS transistor Q3, the grid of the 3rd MOS transistor Q3 is connected to constant-current drive circuit 14.
The level signal that constant-current drive circuit 14 exports, by controlling the grid of driving the 3rd MOS transistor Q3, can control to drive booster circuit 12 to provide described voltage boosting dc voltage to LED strip 13.
Triangular-wave generator 15 and the 3rd comparer U3 is comprised according to the constant-current drive circuit 14 of the embodiment of the present invention.
Triangular-wave generator 15 is for generation of triangular signal.3rd comparer U3 can compare the voltage at the voltage of triangular signal and the first resistor R1 two ends.Wherein, the negative terminal of the 3rd comparer U3 receives the voltage of triangular signal, the anode of the 3rd comparer U3 receives the voltage at the first resistor R1 two ends, when the voltage of triangular signal is greater than the voltage at the first resistor R1 two ends, the output terminal of the 3rd comparer U3 exports the grid of the first level signal to the 3rd MOS transistor Q3 of booster circuit 12, when the voltage of triangular signal is less than the voltage at the first resistor R1 two ends, the output terminal of the 3rd comparer U3 exports the grid of second electrical level signal to the 3rd MOS transistor Q3 of booster circuit 12.
Should be appreciated that, the first level signal can be low level signal, and second electrical level signal can be high level signal.Or the first level signal can be high level signal, second electrical level signal can be low level signal.
Fig. 3 illustrates triangular-wave generator according to an embodiment of the invention.
As shown in Figure 3, triangular-wave generator 15 comprises variohm RT, the first MOS transistor Q1, the first comparer U1, the second comparer U2, the first capacitor C2, the second resistor R2 and the second MOS transistor Q2 according to an embodiment of the invention.
One end of variohm RT receives input voltage Va, the other end of variohm RT is connected to the drain electrode of the first MOS transistor Q1, the source electrode of the first MOS transistor Q1 connects one end of the second resistor R2 and is connected to the negative terminal of the 3rd comparer U3, the other end of the second resistor R2 is connected to the drain electrode of the second MOS transistor Q2, the source electrode electrical ground of the second MOS transistor Q2, the grid of the first MOS transistor Q1 is connected to the output terminal of the first comparer U1, the grid of the second MOS transistor Q2 is connected to the output terminal of the second comparer U2, the negative terminal of the first comparer U1 connects one end of the first capacitor C1 and is connected to the source electrode of the first MOS transistor Q1, the other end electrical ground of the first capacitor C1, the anode of the first comparer U1 receives the first reference voltage V1, the negative terminal of the second comparer U2 is connected to the output terminal of the first comparer U1, the anode of the second comparer U2 receives the second reference voltage V2.
After constant-current drive circuit 14 is energized, its inside can produce a reference voltage V ref(such as, 5V), reference voltage V ref by resistor divider, obtains above-mentioned input voltage Va, the first reference voltage V1 and the second reference voltage V2 again.
As mentioned above, after constant-current drive circuit 14 is energized, obtain input voltage Va, this input voltage Va charges to the first capacitor C1, and the size of the resistance of variohm RT determines the size of the electric current that input voltage Va charges to the first capacitor C1.The voltage that first capacitor C1 charges slowly rises with a certain slope (this slope is relevant with the size of current that the first capacitor C1 charges), when the voltage that the first capacitor C1 charges is greater than the first reference voltage V1, the output terminal output low level of the first comparer U1 is to the grid of the first MOS transistor Q1, make the first MOS transistor Q1 cut-off, input voltage Va stops charging to the first capacitor C1, the low level that the output terminal of the first comparer U1 exports is less than the second reference voltage V2, make the second MOS transistor Q2 conducting, first capacitor C1 is discharged by the second resistor R2, when the voltage that the first capacitor C1 charges reduces and is less than the first reference voltage V1, the output terminal of the first comparer U1 exports high level, make the first MOS transistor Q1 conducting, the low level that the output terminal of the first comparer U1 exports is greater than the second reference voltage V2, make the second MOS transistor Q2 cut-off, input voltage Va starts again to charge to the first capacitor C1, circulation like this, voltage on first capacitor C1 just defines the triangular signal with a certain frequency, the voltage of negative terminal and the first resistor R1 two ends that this triangular signal is input to the 3rd comparer U3 compares, 3rd comparer U3 is according to the grid of comparative result outputs level signals to the 3rd MOS transistor Q3 of booster circuit 12.Notably, the frequency size of this level signal and the frequency equal and opposite in direction of triangular signal.
In addition, the frequency size by regulating the size of input voltage Va to carry out adjusting triangle ripple signal.When input voltage Va becomes large, the charging current of the first capacitor C1 becomes large, the charging voltage of the first capacitor C1 becomes large, make the rate of rise of triangular signal become large, namely the frequency of triangular signal becomes large, when input voltage Va diminishes, the charging current of the first capacitor C1 diminishes, the charging voltage of the first capacitor C1 diminishes, and the rate of rise of triangular signal is diminished, and namely the frequency of triangular signal diminishes.
In addition, when input voltage Va is constant, also carry out the frequency size of adjusting triangle ripple signal by the size of the resistance regulating variohm RT.When the resistance decreasing of variohm RT, the charging current of the first capacitor C1 becomes large, the charging voltage of the first capacitor C1 becomes large, make the rate of rise of triangular signal become large, namely the frequency of triangular signal becomes large, when the resistance of variohm RT becomes large, the charging current of the first capacitor C1 diminishes, the charging voltage of the first capacitor C1 diminishes, and the rate of rise of triangular signal is diminished, and namely the frequency of triangular signal diminishes.
Although Fig. 3 shows triangular-wave generator 15 according to an embodiment of the invention, the present invention is not limited thereto.Also the triangular-wave generator that the controlled system of the large I of frequency of the triangular signal of other output changes can be adopted.
Fig. 4 illustrates liquid crystal display according to an embodiment of the invention.
As shown in Figure 4, liquid crystal display 1 comprises display panels 111 and LED backlight, and display panels 111 is placed on LED backlight.LED backlight provides light source to display panels 111, makes display panels 111 show image.
In sum, LED backlight driving circuit according to an embodiment of the invention, LED backlight and liquid crystal display, by the size of the resistance of the size or variohm RT that periodically regulate input voltage Va, the size controlling the frequency of triangular signal periodically changes, the level signal (i.e. drive singal) of the grid being input to the 3rd MOS transistor Q3 is periodically changed, and then the frequency of drive singal is changed back and forth near centre frequency, the spectrum energy of dispersion drive singal, in EMI test process, be not easy to occur that the peak value of drive singal exceeds standard situation, improve EMI test result.
Although specifically show with reference to its exemplary embodiment and describe the present invention, but it should be appreciated by those skilled in the art, when not departing from the spirit and scope of the present invention that claim limits, the various changes in form and details can be carried out to it.
Claims (9)
1. a LED backlight driving circuit, is characterized in that, comprising:
DC voltage input end, for input direct voltage,
Booster circuit, the DC voltage for being inputted by DC voltage input end is carried out boosting and is exported voltage boosting dc voltage,
LED strip, comprises multiple LED and first resistor of series connection, and receives voltage boosting dc voltage from booster circuit, and wherein, the DC voltage of LED strip normal luminous is less than or equal to the voltage boosting dc voltage of booster circuit output,
Constant-current drive circuit, according to the voltage at the first resistor two ends and the voltage of triangular signal, outputs level signals is to booster circuit;
Wherein, the frequency by regulating the frequency of described triangular signal to regulate described level signal;
Described constant-current drive circuit comprises: triangular-wave generator, for generation of triangular signal; 3rd comparer, for comparing, with outputs level signals to booster circuit the voltage of triangular signal and the voltage at the first resistor two ends;
Described triangular-wave generator comprises: variohm, the first MOS transistor, the first comparer, the second comparer, the first capacitor, the second resistor, the second MOS transistor,
Wherein, one end of variohm receives input voltage, the other end of variohm is connected to the drain electrode of the first MOS transistor, the source electrode of the first MOS transistor connects one end of the second resistor and is connected to the negative terminal of the 3rd comparer, the other end of the second resistor is connected to the drain electrode of the second MOS transistor, the source electrode electrical ground of the second MOS transistor, the grid of the first MOS transistor is connected to the output terminal of the first comparer, the grid of the second MOS transistor is connected to the output terminal of the second comparer, the negative terminal of the first comparer connects one end of the first capacitor and is connected to the source electrode of the first MOS transistor, the other end electrical ground of the first capacitor, the anode of the first comparer receives the first reference voltage, the negative terminal of the second comparer is connected to the output terminal of the first comparer, the anode of the second comparer receives the second reference voltage.
2. LED backlight driving circuit according to claim 1, it is characterized in that, the negative terminal of the 3rd comparer receives the voltage of triangular signal, the anode of the 3rd comparer receives the voltage at the first resistor two ends, when the voltage of triangular signal is greater than the voltage at the first resistor two ends, the output terminal of the 3rd comparer exports the first level signal to booster circuit, when the voltage of triangular signal is less than the voltage at the first resistor two ends, the output terminal of the 3rd comparer exports second electrical level signal to booster circuit.
3. LED backlight driving circuit according to claim 1, is characterized in that, described booster circuit comprises inductor, the 3rd MOS transistor, commutation diode and the second capacitor,
Wherein, one end of inductor is for receiving described DC voltage, the other end of inductor is connected to the positive pole of commutation diode, the drain electrode of the 3rd MOS transistor is connected between inductor and the positive pole of commutation diode, one end of second capacitor is connected to the negative pole of commutation diode, the other end of the second capacitor is connected to the source electrode of the 3rd MOS transistor, and the grid of the 3rd MOS transistor is connected to constant-current drive circuit.
4. LED backlight driving circuit according to claim 1, is characterized in that, by the size regulating the size of described input voltage to regulate the frequency of described triangular signal,
Wherein, when input voltage becomes large, the charging current of the first capacitor becomes large, and the charging voltage of the first capacitor becomes large, makes the rate of rise of triangular signal become large, namely the frequency of triangular signal becomes large, when input voltage diminishes, the charging current of the first capacitor diminishes, and the charging voltage of the first capacitor diminishes, the rate of rise of triangular signal is diminished, and namely the frequency of triangular signal diminishes.
5. LED backlight driving circuit according to claim 1, is characterized in that, is regulated the size of the frequency of described triangular signal by the size of the resistance regulating variohm,
Wherein, when the resistance decreasing of variohm, the charging current of the first capacitor becomes large, and the charging voltage of the first capacitor becomes large, makes the rate of rise of triangular signal become large, namely the frequency of triangular signal becomes large, when the resistance of variohm becomes large, the charging current of the first capacitor diminishes, and the charging voltage of the first capacitor diminishes, the rate of rise of triangular signal is diminished, and namely the frequency of triangular signal diminishes.
6. LED backlight driving circuit according to claim 2, is characterized in that, described first level signal is low level signal, and described second electrical level signal is high level signal.
7. LED backlight driving circuit according to claim 1, is characterized in that, described DC voltage is converted to by the alternating voltage of liquid crystal display outside.
8. a LED backlight, is characterized in that, comprises the LED backlight driving circuit described in any one of claim 1 to 7.
9. a liquid crystal display, is characterized in that, comprises display panels and LED backlight according to claim 8, and wherein, display panels is placed on described LED backlight.
Priority Applications (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310069884.1A CN103218976B (en) | 2013-03-05 | 2013-03-05 | LED backlight driving circuit, LED backlight and liquid crystal display |
| US13/824,397 US9241376B2 (en) | 2013-03-05 | 2013-03-11 | Driver for LED backlight and LED backlight module and liquid crystal display |
| PCT/CN2013/072406 WO2014134836A1 (en) | 2013-03-05 | 2013-03-11 | Led backlight source drive circuit, led backlight source and liquid crystal display |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310069884.1A CN103218976B (en) | 2013-03-05 | 2013-03-05 | LED backlight driving circuit, LED backlight and liquid crystal display |
Publications (2)
| Publication Number | Publication Date |
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| CN103218976A CN103218976A (en) | 2013-07-24 |
| CN103218976B true CN103218976B (en) | 2016-03-30 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201310069884.1A Expired - Fee Related CN103218976B (en) | 2013-03-05 | 2013-03-05 | LED backlight driving circuit, LED backlight and liquid crystal display |
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| Country | Link |
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| CN (1) | CN103218976B (en) |
| WO (1) | WO2014134836A1 (en) |
Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103354086B (en) * | 2013-08-06 | 2015-09-30 | 深圳市华星光电技术有限公司 | LED backlight and liquid crystal display |
| US9058776B2 (en) | 2013-08-06 | 2015-06-16 | Shenzhen China Star Optoelectronics Technology Co., Ltd. | LED backlight source and liquid crystal device |
| CN103400560B (en) * | 2013-08-12 | 2016-12-28 | 深圳市华星光电技术有限公司 | Led backlight drive circuit and liquid crystal display |
| WO2017166183A1 (en) * | 2016-03-31 | 2017-10-05 | 深圳多哚新技术有限责任公司 | Backlight circuit for vr display screen |
| CN109272946B (en) * | 2018-11-16 | 2020-06-05 | 昆山龙腾光电股份有限公司 | Backlight source control circuit and liquid crystal display device |
| CN111930267B (en) * | 2020-09-18 | 2021-02-12 | 深圳市汇顶科技股份有限公司 | Touch control chip, code printing method and electronic equipment |
| WO2022056809A1 (en) | 2020-09-18 | 2022-03-24 | 深圳市汇顶科技股份有限公司 | Touch control chip, coding method, and electronic device |
| CN112201210A (en) * | 2020-10-29 | 2021-01-08 | Tcl华星光电技术有限公司 | Drive circuit, backlight module and display device |
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| KR101565937B1 (en) * | 2008-07-28 | 2015-11-06 | 삼성디스플레이 주식회사 | Backlight assembly display apparatus comprising the same and driving method of the display apparatus |
| JP5412119B2 (en) * | 2009-01-22 | 2014-02-12 | セミコンダクター・コンポーネンツ・インダストリーズ・リミテッド・ライアビリティ・カンパニー | Triangular wave generation circuit |
| JP5043213B2 (en) * | 2010-08-23 | 2012-10-10 | シャープ株式会社 | LED drive circuit and LED illumination lamp using the same |
| KR101875220B1 (en) * | 2011-06-08 | 2018-07-06 | 매그나칩 반도체 유한회사 | Led driver circuit |
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- 2013-03-05 CN CN201310069884.1A patent/CN103218976B/en not_active Expired - Fee Related
- 2013-03-11 WO PCT/CN2013/072406 patent/WO2014134836A1/en active Application Filing
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| CN101340760A (en) * | 2007-07-06 | 2009-01-07 | Nec液晶技术株式会社 | Light emission control circuit, light emission control method, planar lighting device, and liquid crystal display device having the same |
| CN101499787A (en) * | 2008-02-02 | 2009-08-05 | 华润矽威科技（上海）有限公司 | Oscillator circuit having frequency jitter characteristic |
| CN102237794A (en) * | 2010-04-23 | 2011-11-09 | 罗姆股份有限公司 | Control circuit and control method of switch power supply, light-emitting device and electronic device |
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| Publication number | Publication date |
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| CN103218976A (en) | 2013-07-24 |
| WO2014134836A1 (en) | 2014-09-12 |
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